Winter Forecast 2018-19

Here it is! A winter forecast for you to consider as we are now just about a month out from the official beginning to the season. Some have already sent me messages saying I'm late to the game considering the cold weather that showed up early this season. We typically don't release the winter forecast until mid to late November (regardless of what the weather is doing at the time), and it just so turns out this year it tuned off cold before we were able to finish our thoughts.

One of the things I did when putting this together was go back and look at wet Octobers and then see what happened with snowfall later that winter. Here's what I found (from the last 20 years of data)

A wet October was defined by having at least 4" of rain:

1981 - 13.9" of snow that winter

1985 - 11.5"

1998 - 9.3"

2000 - 9.1"

2002 - 25.7"

2007 - 22.1"

2008 - 13.6"

So as you can see above, when October is wet, there is a trend toward normal or above normal winter snowfall.

Here are the other pieces of the winter forecast to consider:

El Nino: 

This is the warmer than normal water found in the Pacific near the Equator. El Nino winters have a TENDENCY to be milder with above normal precipitation. HOWEVER... just because we have an El Nino does NOT mean it will be a warm/wet winter. It also does NOT mean it will be a snowy winter. 

The last El Nino winter was back 2015-16 and it was a BIG one. Water temperatures were about 2.5°C above average, which is just amazing. That winter would go on to have only 4.3"of snow (in Wichita)... most of Kansas didn't get much snow that winter. 

So what we are really concentrating on is a combination of water temperatures in the Pacific, the Arctic Oscillation (more on this in a second), and of course the patterns we've been seeing the last nearly two months. 

Arctic Oscillation:
This is usually an indication of when we will get BIG cold spells across the county. When the Arctic Oscillation (AO) goes negative, bitter cold shows up across the US. When it's positive, we tend to have milder periods.

We expect to have both positive AND negative this winter, but when it goes negative, it will go way down. Take for example what we are seeing heading into December. The AO index continues to be very low, which has me thinking December will start off quite cold in many areas. Details on that in the coming weeks of course.

We are forecasting a cold and wet winter for Kansas, with above normal snowfall and several cold periods ahead. 

One of the weather patterns that will likely repeat this winter should look like this:

A large high pressure in the Gulf of Alaska will allow major cold snaps to take place east of the Rockies. This pattern presented itself last winter from time to time, but I think during this upcoming winter, it will be more pronounced (and last longer). This is also the kind of pattern that delivered the lengthy period of cold weather for the beginning of November.

We will also see a number of storms approach from the west and move right through our area. When that happens (with cold air in place) we will likely see the snow machine go into high gear. I don't really have much confidence in ice storms this winter. I'm don't think we will have a big ice event, but  it's not something we are totally ruling out (just because there will be so much cold air around)

Final thoughts: Consider the following:

1) October was VERY wet

2) Major flooding was experienced across many different areas of the state

3) Earliest measurable snow for Kansas - mid October

4) Very cold to start November

AND... 

5) the last 3 winter have had virtually no major winter storms

I think we are due. You can't go back in the history books and find 4 consecutive winter with less than 5 inches of snow. It's unheard of. The odds are pointing toward more snow this winter, but you can't base the entire forecast off of that idea alone. You do have to weigh that into the equation somewhere. 

Time will tell how our forecast turns out... but I think Kansas may actually have a winter this year.